| 摘要 |
PURPOSE:To check the outline of the operation of a ROM by dividing the memory area of the ROM into two blocks and storing check data in the second block. CONSTITUTION:Control data is stored in a part I of the memory area of a ROM1 of the test object, and check data is stored in a part II. When control is requested, an address signal A from an external controller is inputted to the ROM1 through a selector 2, and a prescribed control output is sent through a gate 4. Unless control is requested, the ROM1 is checked. In this check, the address input of the ROM1 is inputted to the ROM1 through the selector 2, and corresponding output data stored in the part II is sent back and inputted to the selector 2 through a flip flop 3. SInce the time required for the completion of the series of operations is a certain value at the normal operation time, this time is monitored by a counter to discriminate whether the operation is normal or abnormal.
|
